| 1 | package release |
| 2 | |
| 3 | import ( |
| 4 | "github.com/carlosframework/platform/internal/rootstate" |
| 5 | "os" |
| 6 | "path/filepath" |
| 7 | "strings" |
| 8 | ) |
| 9 | |
| 10 | func GenerationFileProof(path string, before, after rootstate.FileIdentity) bool { |
| 11 | if before.Same(after) { |
| 12 | return true |
| 13 | } |
| 14 | source := func(id rootstate.FileIdentity) (string, bool) { |
| 15 | root, e1 := generationProofUnescape(id.MountRoot) |
| 16 | point, e2 := generationProofUnescape(id.MountPoint) |
| 17 | if e1 != nil || e2 != nil || !filepath.IsAbs(root) || !filepath.IsAbs(point) || filepath.Clean(root) != root || filepath.Clean(point) != point { |
| 18 | return "", false |
| 19 | } |
| 20 | rel, err := filepath.Rel(point, path) |
| 21 | if err != nil || !filepath.IsLocal(rel) { |
| 22 | return "", false |
| 23 | } |
| 24 | return filepath.Join(root, rel), true |
| 25 | } |
| 26 | if before.SameMountNamespace(after) || before.MountLineage == "" || after.MountLineage == "" || before.MountLineage == after.MountLineage || !strings.HasSuffix(before.MountLineage, "\n"+after.MountLineage) { |
| 27 | return false |
| 28 | } |
| 29 | beforePoint, e1 := generationProofUnescape(before.MountPoint) |
| 30 | afterPoint, e2 := generationProofUnescape(after.MountPoint) |
| 31 | rel, err := filepath.Rel(afterPoint, beforePoint) |
| 32 | if e1 != nil || e2 != nil || err != nil || rel == "." || !filepath.IsLocal(rel) { |
| 33 | return false |
| 34 | } |
| 35 | a, ok1 := source(before) |
| 36 | b, ok2 := source(after) |
| 37 | if !ok1 || !ok2 || a != b { |
| 38 | return false |
| 39 | } |
| 40 | after.MountRoot, after.MountPoint, after.MountLineage = before.MountRoot, before.MountPoint, before.MountLineage |
| 41 | return before.Same(after) |
| 42 | } |
| 43 | |
| 44 | func generationProofUnescape(s string) (string, error) { |
| 45 | var out strings.Builder |
| 46 | for i := 0; i < len(s); i++ { |
| 47 | if s[i] != '\\' { |
| 48 | out.WriteByte(s[i]) |
| 49 | continue |
| 50 | } |
| 51 | if i+3 >= len(s) { |
| 52 | return "", os.ErrPermission |
| 53 | } |
| 54 | switch s[i : i+4] { |
| 55 | case "\\040": |
| 56 | out.WriteByte(' ') |
| 57 | case "\\011": |
| 58 | out.WriteByte('\t') |
| 59 | case "\\012": |
| 60 | out.WriteByte('\n') |
| 61 | case "\\134": |
| 62 | out.WriteByte('\\') |
| 63 | default: |
| 64 | return "", os.ErrPermission |
| 65 | } |
| 66 | i += 3 |
| 67 | } |
| 68 | return out.String(), nil |
| 69 | } |
| 70 | |
amadan